Round hay bales are too large and heavy for manual handling and thus need be handled by machinery. These bales need be moved from a field site to a barn, storage or usage site. Furthermore, they need to be unrolled for use in feeding at a feed site. Because of their size and shape the machinery need be specially adapted to the dimensions and characteristics of the round hay bales. Examples of such machinery in the prior art may be generally classified as transport devices and as dual purpose loader-unrollers.
Typical transport devices include U.S. Pat. Nos. 4,095,706--H. B. Schwien et al.--June 20, 1978 and 3,944,095--R. L. Brown--Mar. 16, 1976 and provide a trailer with a winch for grasping and swinging a round bale up for transport by pivoting a rack engaging the bale to raise it off the ground behind the trailer for transport, and U.S. Pat. No. 4,194,863--J. D. Vansickle et al.--Mar. 25, 1980 provides a set of lifting arms operated by hydraulic cylinders on each side of a tractor to raise a bale off the ground in front of the tractor.
The unrolling of bales has been generally achieved by simply using the transport device to lower the bale on the ground behind the transport device to unroll the layer by rolling the bale on the ground as shown in U.S. Pat. Nos. 4,044,963--D. L. Hostetler--Aug. 30, 1977; 4,049,140--G. L. Roose--Sept. 20, 1977; and 4,090,624--V. R. Krein et al.--May 23, 1978.
These prior art bale handlers, however, have not resolved many critical problems afforded because of the characteristics of the bales and the manner of use and storage.
For example, it is cumbersome and unsatisfactory to unroll the bales by rolling on the ground. First they must be oriented in the right direction for unrolling. Then they need a lot of room for unrolling. Then if hay is to be fed in a rack or barn, the unrolled hay has to be rehandled.
Another unresolved problem in picking up rolls placed at random in a field is that the rolls are generally spiked by penetrating rods at each end center roll and then handled. However, with varying and uneven ground contour, it is necessary to resposition bales when one of the spikes would be off-center in a tilted rest position with respect to the transport lifter.
Also when it is desired to load and transport the bales, the matter of load and balance is most important in terms of trailer coupling, riding security and safety, etc. In particular, if more than one bale is to be transported, the matter of lifting and positioning the bales requires very complex mechanisms. To be more explicit, it is most difficult with a simple reliable mechanism, for example, to lift a bale from the ground to place it on a trailer bed for transport. Consider that an arc movement of the order of 160.degree. is necessary, and that about the greatest art available from simple pivoting movement responsive to a hydraulic ram is only about 120.degree..
Furthermore, it is difficult to provide a completely self contained, simple low cost mechanism fully powered for the lifting and handling of the rolls. For example, if hydraulic mechanisms are used they in the prior art required a compatible truck or tractor equipped hydraulic system, which is not always available and which if used thus necessitates expensive transport equipment. Clearly the prior art did not know how to provide a low cost comprehensive self contained trailer system that could simply be transported by a pick-up truck, or the like.
Accordingly, it is an objective of this invention to resolve the aforesaid shortcomings of the prior art and to provide improved self contained hydraulic actuated round bale handling equipment trailer mounted for transport by any convenient mode of transport, including pick-up truck.